Summertime additions Albert Haynesworth (listed at 350 pounds) and Shaun Ellis (290) made their Patriots debuts in Thursday night’s 18-17 preseason-ending loss to the New York Giants at Gillette Stadium.

Starting in a four-man front with Vince Wilfork and Andre Carter, Haynesworth (right tackle) contributed three tackles to the Patriots’ cause, while Ellis (left end) registered a first-half sack, taking David Carr down for a 7-yard loss late in the second quarter.

“It was good,” said Ellis, the free agent who, in the aftermath of a hip injury graduated from the physically unable to perform list to practice after coming to New England from the New York Jets. “It was fun.”

Acquired from Washington in exchange for a fifth-round pick in the 2013 NFL Draft, Haynesworth also missed the bulk of training camp, speculation being that the Patriots were practicing knee maintenance with the 30-year-old.

A two-time Pro Bowler with the Tennessee Titans, Haynesworth came to New England following two underachieving seasons with the Redskins, who handed him the keys to the vault when he hit the free-agent market in 2009.

“It was great,” Haynesworth said of his first action of the season. “I need to knock off a lot of rust. I’ve kind of been just rusting just sitting in D.C. so I need to get back and get back to that playing form I had when I was with the Titans.”

Haynesworth said the depth the team boasts in the defensive line will allow him the opportunity to pace himself in New England.

“What we do here – which is pretty good, unbelievable, it’ll help you – is we rotate a lot,” said Haynesworth. “We’ve got a lot of depth. We had good depth at Tennessee, but here we have great depth. We have guys that on any other team would start.

“Like our coach tells us, like ‘Peppy’ (Pepper Johnson) tells us, ‘Go as hard as you can however many plays. If that’s three or four plays, do that, come out. We have somebody else. (We’ll) send in another wave of attack.’

“So that’s what we’re going to do. I’m just going to play as hard as I possibly can. When I get gassed, I’m going to come out.”

Haynesworth says he could get used to the Patriots’ way.

“I feel right at home here,” said Haynesworth. “I wish I was here earlier.”

It slipped away: Capitalizing on a couple of turnovers – safety Patrick Chung’s recovery of a Domenik Hixon fumble and 18-yard return to the 1 and cornerback Devin McCourty’s interception of a Carr pass and 18-yard return to the New York 33 – and the fact that their starters were lining up against their opponents’ backups, the Patriots forged a quick double-digit lead against the Giants.

Page 2 of 2 - For the record, BenJarvus Green-Ellis’ first of two 1-yard touchdown runs (20 seconds into the first quarter) and Stephen Gostkowski’s 31-yard field goal made it 10-0 before the game was five minutes old.

The Patriots built a 17-3 lead before their junior varsity squandered it in the fourth quarter, surrendering it on a fake punt (Da’Ral Scott went 65 yards for a touchdown), a fumble recovery that was returned for a TD (defensive back Derrick Martin went 11 yards) and a successful two-point conversion on a pass from Ryan Perrilloux to Jerrel Jernigan.

The fall of Meriweather?: One of the more bizarre developments of the game was the sight of Brandon Meriweather, the two-time Pro Bowl safety, on the field in the fourth quarter as part of a secondary with James Ihedigbo (signed earlier this month), Antwaun Molden (signed Wednesday) and Ross Ventrone (released and re-signed this summer).

Asked after the game if he was happy with his situation, Meriweather responded: “I don’t know my situation. I think our coaches do a great job of rotating all of us in and playing a lot of guys, getting a lot of guys a lot of time with other people to see how they play together.”

When asked his reaction to James Sanders’ release on Monday and the overall makeup of the safety position, Meriweather said: “To be honest, I really don’t even want to talk about it.”

Remembering 9/11: Due to open the regular season on the road (at Miami Sept. 12), the Patriots observed the upcoming 10th anniversary of 9/11 prior to Thursday night’s game.

As part of the remembrance, former guard Joe Andruzzi, his three New York City firefighter brothers (Billy, Jimmy and Marc) and their father (Bill Sr.), a former New York City police officer, served as honorary team captains and participated in the pregame coin toss.

It was 12 days after the 9/11 attacks, on Sept. 23, 2001, that the Andruzzis were recognized on the field at the old Foxboro Stadium prior to the Patriots’ 10-3 loss to the New York Jets that day.

Thursday night’s tribute also involved approximately 200 members of all five branches of the military (Army, Navy, Air Force, Marines and Coast Guard), police and firefighters.

Locals take the field: In celebration of USA Football month in August, approximately 100 youth players from Plymouth (two teams), Bellingham and Arlington scrimmaged on the Gillette Stadium playing surface at halftime of Thursday night’s game.